No agreement has been reached in Piven’s grievance hearing, regarding the “Entourage” star’s mysterious mercury poisoning.

Piven appeared at the session requested by the producers of “Speed-the-Plow” to defend his much-snickered-at claim that high levels of mercury in his bloodstream, brought on by a passion for sushi, forced him to abandon the Broadway show. (READ: Piven’s Poisonal Plea)

But after hearing from both parties, a panel composed of Actors’ Equity and Broadway League representatives were unable to reach a unanimous decision. A joint statement issued by the union and the Broadway producers’ trade association said “the producers have the right, as a next step, to proceed to arbitration.”

The producers could not immediately be reached for comment.

Piven’s spokeswoman, Samantha Mast, issued a statement saying: “Mr. Piven is hopeful that the producers will ultimately recognize that he did the right thing by listening to the instructions from his doctors … who told him to stop the play immediately and undergo enforced rest, rather than continuing to perform and risk dire health consequences.”

“Speed-the-Plow” opened last October to generally enthusiastic notices and by the time the revival ended its limited engagement Feb. 22 at the Ethel Barrymore Theatre, it had recouped its $2.26 million production costs.

Three different actors – understudy Jordan Lage, Norbert Leo Butz and William H. Macy – followed Piven in the role of movie mogul Bobby Gould. Mamet’s three-character play about Hollywood glamour, sex and power, also starred Elisabeth Moss of AMC’s “Mad Men” and Raul Esparza.